Bugfixes / Tutorial cleanup

core/src/mindustry/entities/Damage.java

@@ -25,6 +25,7 @@ public class Damage{
     private static Rect rect = new Rect();
     private static Rect hitrect = new Rect();
     private static Vec2 tr = new Vec2();
+    private static Seq<Unit> units = new Seq<>();
     private static GridBits bits = new GridBits(30, 30);
     private static IntQueue propagation = new IntQueue();
     private static IntSet collidedBlocks = new IntSet();
@@ -117,14 +118,16 @@ public class Damage{
             Building tile = world.build(cx, cy);
             boolean collide = tile != null && collidedBlocks.add(tile.pos());
 
-            if(collide && tile.team != team && tile.collide(hitter)){
-                tile.collision(hitter);
-                hitter.type.hit(hitter, tile.x, tile.y);
-            }
+            if(hitter.damage > 0){
+                if(collide && tile.team != team && tile.collide(hitter)){
+                    tile.collision(hitter);
+                    hitter.type.hit(hitter, tile.x, tile.y);
+                }
 
-            //try to heal the tile
-            if(collide && hitter.type.collides(hitter, tile)){
-                hitter.type.hitTile(hitter, tile, 0f, false);
+                //try to heal the tile
+                if(collide && hitter.type.collides(hitter, tile)){
+                    hitter.type.hitTile(hitter, tile, tile.health, false);
+                }
             }
         };
 
@@ -161,20 +164,27 @@ public class Damage{
         rect.height += expand * 2;
 
         Cons<Unit> cons = e -> {
-            if(!e.checkTarget(hitter.type.collidesAir, hitter.type.collidesGround)) return;
-
             e.hitbox(hitrect);
 
             Vec2 vec = Geometry.raycastRect(x, y, x2, y2, hitrect.grow(expand * 2));
 
-            if(vec != null){
+            if(vec != null && hitter.damage > 0){
                 effect.at(vec.x, vec.y);
                 e.collision(hitter, vec.x, vec.y);
                 hitter.collision(e, vec.x, vec.y);
             }
         };
 
-        Units.nearbyEnemies(team, rect, cons);
+        units.clear();
+
+        Units.nearbyEnemies(team, rect, u -> {
+            if(u.checkTarget(hitter.type.collidesAir, hitter.type.collidesGround)){
+                units.add(u);
+            }
+        });
+
+        units.sort(u -> u.dst2(hitter));
+        units.each(cons);
     }
 
     /**

core/src/mindustry/entities/bullet/RailBulletType.java

@@ -1,5 +1,7 @@
 package mindustry.entities.bullet;
 
+import arc.math.geom.*;
+import arc.util.*;
 import mindustry.content.*;
 import mindustry.entities.*;
 import mindustry.gen.*;
@@ -15,36 +17,54 @@ public class RailBulletType extends BulletType{
     /** Multiplier of damage decreased per health pierced. */
     public float pierceDamageFactor = 1f;
 
+    public float length = 100f;
+
+    public float updateEffectSeg = 20f;
+
     public RailBulletType(){
         pierceBuilding = true;
         pierce = true;
         reflectable = false;
         hitEffect = Fx.none;
         despawnEffect = Fx.none;
+        collides = false;
+        lifetime = 1f;
+    }
+
+    @Override
+    public float range(){
+        return length;
     }
 
     void handle(Bullet b, Posc pos, float initialHealth){
         float sub = initialHealth*pierceDamageFactor;
 
-        if(sub >= b.damage){
-            //cause a despawn
-            b.remove();
+        if(b.damage <= 0){
+            b.fdata = Math.min(b.fdata, b.dst(pos));
+            return;
+        }
+
+        if(b.damage > 0){
+            pierceEffect.at(pos.getX(), pos.getY(), b.rotation());
+
+            hitEffect.at(pos.getX(), pos.getY());
         }
 
         //subtract health from each consecutive pierce
         b.damage -= Math.min(b.damage, sub);
-
-        if(b.damage > 0){
-            pierceEffect.at(pos.getX(), pos.getY(), b.rotation());
-        }
-
-        hitEffect.at(pos.getX(), pos.getY());
     }
 
     @Override
-    public void update(Bullet b){
-        if(b.timer(1, 0.9f)){
-            updateEffect.at(b.x, b.y, b.rotation());
+    public void init(Bullet b){
+        super.init(b);
+
+        b.fdata = length;
+        Damage.collideLine(b, b.team, b.type.hitEffect, b.x, b.y, b.rotation(), length, false);
+        float resultLen = b.fdata;
+
+        Vec2 nor = Tmp.v1.set(b.vel).nor();
+        for(float i = 0; i <= resultLen; i += updateEffectSeg){
+            updateEffect.at(b.x + nor.x * i, b.y + nor.y * i, b.rotation());
         }
     }